U.S. patent application number 12/336845 was filed with the patent office on 2009-06-25 for structure for use as part of a medical device.
This patent application is currently assigned to Boston Scientific Scimed, Inc.. Invention is credited to Isaac Ostrovsky.
Application Number | 20090160112 12/336845 |
Document ID | / |
Family ID | 40348134 |
Filed Date | 2009-06-25 |
United States Patent
Application |
20090160112 |
Kind Code |
A1 |
Ostrovsky; Isaac |
June 25, 2009 |
STRUCTURE FOR USE AS PART OF A MEDICAL DEVICE
Abstract
A low cost, flexible, torqueable structure for use as at least a
portion of a medical device comprises a coil formed of a wound
element. The coil includes a plurality of adjacent windings.
Connected portions of a region between the adjacent windings are
formed (by, for example, laser welding) such that torque can be
transmitted between adjacent windings.
Inventors: |
Ostrovsky; Isaac;
(Wellesley, MA) |
Correspondence
Address: |
COOLEY GODWARD KRONISH LLP;ATTN: Patent Group
Suite 1100, 777 - 6th Street, NW
WASHINGTON
DC
20001
US
|
Assignee: |
Boston Scientific Scimed,
Inc.
Maple Grove
MN
|
Family ID: |
40348134 |
Appl. No.: |
12/336845 |
Filed: |
December 17, 2008 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
61015105 |
Dec 19, 2007 |
|
|
|
Current U.S.
Class: |
267/155 ;
29/592 |
Current CPC
Class: |
A61B 1/0055 20130101;
A61M 25/0013 20130101; Y10T 29/49 20150115; A61M 25/0043 20130101;
A61M 2025/09066 20130101; A61M 25/0054 20130101 |
Class at
Publication: |
267/155 ;
29/592 |
International
Class: |
F16F 1/06 20060101
F16F001/06; B23P 11/00 20060101 B23P011/00 |
Claims
1. A structure for use as at least a portion of a medical device
comprising: a coil formed of a wound element, the coil including a
plurality of adjacent windings; and a material disposed in at least
a portion of a region between adjacent windings, the material
connecting adjacent windings of the coil and thereby allowing
torque to be transmitted between adjacent windings.
2. The structure of claim 1 wherein the element comprises a flat
wire, the flat wire having a width and a thickness.
3. The structure of claim 2 wherein the flat wire comprises
metal.
4. The structure of claim 1 wherein the material comprises a laser
weld.
5. The structure of claim 1 wherein the material is a plurality of
separate segments of material.
6. The structure of claim 1 wherein the material is a continuous
strip of material.
7. The structure of claim 1 wherein the material comprises an
adhesive.
8. The structure of claim 1 wherein the material comprises
solder.
9. The structure of claim 1 wherein the material comprises
epoxy.
10. The structure of claim 1 wherein the material is a plurality of
rivets.
11. The structure of claim 1 further comprising an outer sheath
disposed over the coil.
12. The structure of claim 11 wherein the sheath is heat shrunk to
fit over the coil.
13. The structure of claim 1 further comprising an inner tube,
wherein the coil fits over the inner tube.
14. The structure of claim 1 wherein the coil has a proximal end
and a distal end and a lumen extending from the proximal to the
distal end of the coil.
15. A structure for use as at least a portion of a medical device
comprising: a coil formed of a wound element, the coil including an
outer surface defined by the outer surface of each of the windings
of the element; and a material disposed windingly on the outer
surface of the coil and extending along a length of the coil, the
material connecting, along the length, adjacent windings of the
coil to each other.
16. A structure for use as at least a portion of a medical device
comprising: a coil formed of a wound element; and a material
disposed in a winding pattern along a length of the coil and
between at least some of the adjacent windings of the coil, the
material connecting, along the length, at least some of the
adjacent windings of the coil to each other.
17. A method of making a structure for use as at least a portion of
a medical device comprising: providing a coil formed of a wound
element, the coil including a plurality of adjacent windings each
having a pitch; and forming connected portions of a region between
adjacent windings such that torque can be transmitted between
adjacent windings.
18. The method of claim 17 wherein the forming step comprises laser
welding.
19. A method of making a structure for use as at least a portion of
a medical device comprising: providing a coil formed of a wound
element, the coil including an outer surface defined by the outer
surface of each of the windings of the coil; and disposing a
material windingly on the outer surface of the coil such that the
material extends along a length of the coil and connects adjacent
windings of the coil to each other along the length.
20. A method of making a structure for use as at least a portion of
a medical device comprising: providing a coil formed of a wound
element; and disposing a material in a winding pattern along a
length of the coil and between at least some of the adjacent
windings of the coil such that the material connects the at least
some of the adjacent windings of the coil to each other.
Description
CROSS-REFERENCE TO RELATED CASES
[0001] This application claims priority to, and the benefit of
Provisional U.S. Patent Application Ser. No. 61/015,105, filed Dec.
19, 2007, the entirety of which is incorporated herein by
reference.
TECHNICAL FIELD
[0002] The present invention generally relates to a low cost,
flexible, and torqueable structure for use as part of a medical
device.
BACKGROUND INFORMATION
[0003] Medical devices are commonly used to access remote regions
of the body to deliver diagnostic or therapeutic agents to those
regions and to perform surgical procedures on those regions. For
example, endoscopes may use body airways and canals to access the
colon, esophagus, stomach, urethra, bladder, ureter, kidneys,
lungs, bronchi, uterus, and other organs. Catheters may use the
circulatory system as pathways to access treatment sites near the
heart or may use the urinary tract to access urinary regions.
[0004] Some medical devices can be introduced into the vasculature
of the body of the patient through a large artery such as those
found in the groin or in the neck of a human or other mammal. These
devices are often passed through ever-narrower arteries until they
can reach the operative site inside the body. Many such pathways
may curve, loop around, and even wind back.
[0005] Catheters are described in various patents, published patent
applications, and other publications. See, for example, U.S. Pat.
No. 3,924,632 and published U.S. Patent Application
2006/0111649.
SUMMARY OF THE INVENTION
[0006] The present invention generally relates to a low cost,
flexible, and torqueable structure for use as part of a medical
device and also methods of making such a structure. The structure
can be manufactured without the use of expensive tubing or costly,
time-consuming, and complicated laser cutting operations, and also
without the need for one of more layers (of, for example, braided
wire or other such material), yet still achieved the desired
flexibility and torqueability. The structure can be formed simply
of a coiled wire that is fed through a laser cut machine to join or
weld together at least some of the adjacent turns of the coil. The
laser cut machine would be set to apply an appropriate amount of
laser energy to fuse or weld those adjacent turns but not to cut
thought the coiled wire, and the coil would be rotated as it is fed
longitudinally through the machine to create a winding pattern of
weld locations.
[0007] In one aspect, the invention features a structure for use as
at least a portion of a medical device, and the structure comprises
a coil formed of a wound element. The coil includes a plurality of
adjacent windings and each winding has a pitch. A material is
disposed in a portion of the region between adjacent windings such
that the material connects adjacent windings of the coil and allows
torque to be transmitted between adjacent windings.
[0008] The wound element can be a flat wire, and the flat wire can
be metal or other synthetic or natural material. The element
typically will be made of one or more materials that are acceptable
for use within the body of a patient.
[0009] The structure can include an outer sheath disposed over the
coil. The outer sheath can be made from a variety of known
materials and can be heat shrunk to fit over the coil. The
structure can also include and inner tube, disposed in the inside
of the coil and with a proximal end and a distal end and a lumen
extending from the proximal to the distal end of the coil.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] For a fuller understanding of the nature and operation of
various embodiments according to the present invention, reference
is made to the following description taken in conjunction with the
accompanying drawing figures which are not necessarily to scale and
wherein like reference characters denote corresponding or related
parts throughout the several views.
[0011] FIG. 1 is a diagram of a section of laser cut tubing.
[0012] FIG. 2 is a diagram of a coil.
[0013] FIG. 3 is a diagram depicting the a coil used as part of an
endoscope.
[0014] FIG. 4 is a diagram depicting one aspect of the low cost,
flexible, torqueable structure.
[0015] FIG. 5 is a diagram depicting an alternative embodiment of
the low cost, flexible, torqueable structure.
[0016] FIGS. 6a-6e are diagrams of the structure of FIG. 5
depicting the material disposed windingly along the outer surface
of the coil.
[0017] FIG. 7 is a diagram depicting the material disposed in
straight lines along the length of the coil.
[0018] FIG. 8 is a diagram depicting flexing, torqueing, and
pushing of the structure.
[0019] FIG. 9 is a diagram depicting a plurality of rivets
connecting adjacent windings of the coil.
[0020] FIG. 10a is a diagram depicting the material connecting a
portion of the space on the outer surface of the windings of the
coil, the connected portion being greater than the unconnected
portion.
[0021] FIG. 10b is a diagram depicting the material connecting a
portion of the space on the outer surface of the windings of the
coil, the connected portion being smaller than the unconnected
portion.
[0022] FIG. 11 is a diagram depicting the material flush with the
outer diameter of the coil.
[0023] FIG. 12 is a diagram depicting a plurality of strips of the
material disposed windingly along the coil.
[0024] FIG. 13a is a diagram depicting the structure with an outer
sheath.
[0025] FIG. 13b is a diagram depicting the structure with an inner
core.
DESCRIPTION
[0026] As indicated above, the present invention relates to a
flexible and torqueable structure for use as part of a medical
device. Such a structure can be manufactured without the use of
expensive tubing or costly, time-consuming, and complicated laser
cutting operations, and also without the need for one of more
layers, yet still achieved the desired flexibility and
torqueability.
[0027] Referring now to FIG. 1, a structure 198 for use as at least
part of a medical device comprises a tube 100 that is laser cut for
the purpose of producing a flexible torqueable hollow shaft. The
laser cutting is made in a spiral path with alternating cut 115 and
un-cut 119 portions. The cut pattern is specified by the pitch and
the length of the cut 115 and un-cut 119 portions.
[0028] The length of the cut 115 portion of the spiral path is
generally several times greater than the un-cut 119 portion. The
spiral path of the cut 115 and un-cut 119 portions can be specified
in terms of the radial angle. The cut pattern can be defined by the
pitch and the radial angle of the cut and un-cut portions. For
example, the pattern shown in FIG. 1 has a pitch of 0.035'' and the
cut/un-cut portions are specified as 220.degree./45.degree.. The
length and width of the cuts, as well as the relative ratio of
cut-to-uncut portions can be varied to impart different
flexibilities at different parts of the structure 198. Stainless
steel tubing with such laser is available from Creganna Medical
Device Company of Parkmore West, Galway, Ireland.
[0029] Referring now to FIG. 2, a flat-wire wound coil 102 is
shown. The coil 102 can be formed by winding a flat wire into a
tubular shape. The coil 102 is flexible, but does not transmit
torque well from one end of the coil to the other end.
[0030] The coil 102 can be used as a portion of a medical device
500 such as an endoscope as shown in FIG. 3. The coil 102 can
impart flexibility to the endoscope 500, as it makes its way from
the exterior body opening 502, through the body pathway 504, and to
the operative site 506.
[0031] The endoscope 500 can include a surgical component 508 and
an imaging component 510. Any of a variety of surgical components
can be passed into a working channel of the endoscope 500 including
biopsy forceps, snares, fulguration probes, and other tools. The
imaging component 510 can produce an image that is displayed to an
operator of the endoscope 500. The imaging component 510 can
include an objective lens and fiber optic imaging light guide
communicating with a camera located at a proximal end 514 of the
endoscope 500, or an imaging camera chip at a distal end 516. The
endoscope 500 can be run over a guide wire 512 to facilitate
placement of the endoscope within a patient. The terms proximal and
distal require a point of reference. In this application, the point
of reference is the perspective of the user. Therefore, the term
proximal will always refer to an area closest to the user, whereas
distal will always refer to an area away from the user.
[0032] The endoscope 500 may be uniformly flexible or could
comprise a plurality of segments having varying degrees of
flexibility or rigidity. The endoscope 500 includes an outer sheath
520 disposed on the outside of the flexible coil 102 to provide a
smooth exterior surface. The outer sheath 520 can be made from
soft, thin polyurethane, LLDPE, silicon, pellethane, polyurethane
or other approved biocompatible materials such as polyethylene,
polypropylene or polyvinyl alcohol. Additionally, the outer sheath
520 can be coated with a hydrophilic, lubricious coating such as
HYDROPASS.TM. hydrophilic coating available from Boston Scientific
Corporation, of Natick, Mass., and described in U.S. Pat. Nos.
5,702,754 and 6,048,620, which are herein incorporated by
reference.
[0033] The coil 102 could also be used as at least a portion of a
catheter, and the catheter can include an infusion pump for pumping
liquids to a site within the body. The coil 102 also could be used
as at least a portion of a medical stent.
[0034] Some endoscopes and catheters have means for steering or
deflecting the distal tip of the endoscope to follow the pathway of
the anatomy under examination such as the colon, bladder, kidney,
and heart. Deflection or articulation is often a desirable
characteristic in these types of medical devices to minimize
friction force and trauma to the surrounding tissue, and to survey
targeted examination sites. Navigation of the endoscope through
various areas within a patient improves the success of the
examination and minimizes pain, side effects, risk, or sedation to
the patient. Therefore, in addition to imparting flexibility to
endoscope or a catheter, it would be desirable to provide a coil
that is flexible, but also one that has the ability to transmit
torque from the proximal end of the coil to the distal end.
[0035] FIG. 4 shows an alternative embodiment of a structure 98 for
use with a medical device. The structure 98 performs a similar
function as the structure 198 described above. In this embodiment,
the structure 98 comprises an element 100 that is wound into a coil
102. The element 100 can be, for example, a flat wire with a
rectangular cross-section. The flat-wire can have a rectilinear
profile or can have rounded edges. In one embodiment, the width of
the flat-wire can be varied to control the flexibility and
torqueability along a length of the coil. In another embodiment,
the width can be held constant to produce uniform flexibility and
torqueability along a length of the coil. The thickness of the
flat-wire can also be varied to control the flexibility and
torqueability along a length of the coil or can be held constant to
produce uniform flexibility and torqueability along a length of the
coil. In short, the element 100 that is wound to form the coil 102
can have a variety of widths and cross-sectional shapes and the
shape can vary along the length of the coil 102.
[0036] The element 100 can be made of any of a variety of
materials, including metallic materials that offer superior
strength-to-weight rations. Examples of metals include stainless
steel and tungsten alloys, and other more malleable alloys,
including gold, platinum, palladium, rhodium, etc. The class of
alloys know as super-elastic alloys can also be used, including
titanium. Other materials, including synthetic and natural
materials, can also be used, such as plastic. The element 100
typically will be made of one or more materials that are acceptable
for use within the body of a patient.
[0037] The coil 102 can be manufactured using any of a number of
methods, including winding the element around a barrel forming a
plurality of windings 106. A portion of the region between adjacent
windings are then welded or otherwise adhered to each other to form
connected 123 and unconnected 125 portions. The connected portions
123 and unconnected portions 125 shown in FIG. 4 are similar to the
uncut 119 portions and cut 115 portions shown in FIG. 1,
respectively, in that the unconnected portions 125 behave
essentially the same as the cut portions 115 and the connected
portions 123 behave essentially the same as the uncut portions
119.
[0038] The process of connecting some of the region between
adjacent windings can be accomplished with a laser in a similar
manner as the laser cutting of tubing described above. The wound
coil 102 can be continuously fed into a laser welding machine and
be welded in a spiral path with alternating welded and unwelded
portions. The performance of the welded coil structure 98 would be
similar to cut tube structure 198 described above.
[0039] One advantage of the welded structure 98 over the cut tubing
structure 198 is the manufacturing time on the laser
cutting/welding machine. In order to provide the greatest amount of
flexibility, the radial angle of the cut/unwelded portion is
generally greater than the radial angle of the uncut/welded
portion. For example, in FIGS. 1 and 4, the radial angle of the
cut/unwelded portion is 220.degree. and the radial angle of the
uncut/welded portion is 45.degree., i.e., almost 5 times greater.
Therefore, the time spent laser cutting a tube would be almost 5
times longer than the time laser welding the wound tube. This
reduced manufacturing time translates into reduced manufacturing
costs.
[0040] The material used to make the tubing is also generally
different from the flat wire used to make the wound coil. The cost
of the material for the cut tubing is generally much higher than
that of the wound coil. Also, there is a greater variety of
materials for the wound coil so the performance of the structure
including flexibility, torqueability, strength and durability,
would be superior to the cut tubing design. Finally, the
availability of a greater variety of materials might allow for, for
example, thinner walls of the structure 98, which translates into a
bigger inside diameter and smaller outside diameter which is always
a desirable characteristic in medical devices such as endoscopes
and catheters.
[0041] In another embodiment, the wound coil 102 includes a
material disposed on the outer surface of the wound coil 102.
Referring now to FIG. 5, the coil 102 includes an outer surface
104, defined by the outer surface of each of the windings 106 of
the element 100. A material 108 is disposed windingly on the outer
surface 104 of the coil 102, and the material 108 extends
longitudinally along a length 112 of the coil 102. The length 112
shown is less than the entire length of the coil 102, but the
length 112 could be the entire length of the coil 102 or any
portion thereof. The material 108 connects adjacent windings 114 of
the coil 102 to each other at a location 116 on the outer surface
104 of the coil 102.
[0042] The material 108 can be disposed using a variety of methods.
For example, a weld-applying machine can be used to dispose the
material 108 on the outer surface 104 of the coil 102 as the coil
is rotated and advanced longitudinally. Referring now also to FIGS.
6a-6e, the material 108 is a strip of material 700 disposed
windingly 702, 704, 706, 708 along the outer surface 104 of the
coil 102. The material 108 can also be disposed in a straight line
or in a series of separate straight lines 800 as shown in FIG. 7.
The material 108 can be made from a variety of materials,
including, for example, adhesive, solder, or an epoxy.
[0043] Referring now to FIG. 8, the material 108 can alternatively
be disposed at discrete points along the length of the coil 102. A
laser spot welding machine can dispose the material 108 on the
outer surface of the coil to connect adjacent windings of the coil.
The material disposed along the windings of the coil produces a
structure that is flexible 300 and torqueable 302.
[0044] In other embodiments, the material 108 can be a connecting
element, including a rivet or a hinge. As shown in FIG. 9, the
material 108 can be a plurality of rivets 900 connecting the
adjacent windings of the coil.
[0045] In some embodiments, the material 108 can connect a portion
of the outer surface 1002 of the adjacent windings 1004 of the coil
that is longer than an unconnected portion of the outer surface
1002 of the adjacent windings 1004 of the coil as shown in FIG.
10a. Alternatively, as shown in FIG. 10b, the material 108 can
connect a portion of the outer surface 1002 of the adjacent
windings 1004 of the coil that is shorter, or equivalent to the
unconnected portion of the outer surface 1002 of the adjacent
windings 1004 of the coil.
[0046] The outer diameter of the coil 1101 can be defined as the
cross-sectional width of the coil from one side of the outer
surface of the coil to the opposite side of the outer surface of
the coil. The material 1100 can be disposed in between the windings
of the coil along a length of the coil. In one embodiment, the
material disposed in between the windings can be designed to be
flush 1102 with the outer surface 1104 of the coil 1106, as shown
in FIG. 11. This minimizes the outer diameter of the coil 1101,
which can reduce the overall diameter of the medical device, thus
making the medical device capable of use in smaller body pathways.
The outer diameter of the coil 1101 can also be varied along the
length of the coil.
[0047] In one embodiment shown in FIG. 12, a plurality of strips of
material 1200 can be disposed on the outer surface 104 of the coil
102, each strip disposed in a different configuration from the
other strips, and extending longitudinally along a length 112 of
the coil 102. The strips of material connect along a length 112,
adjacent windings 106 of the coil 102. Each strip of the material
can be divided into a plurality of separate segments connecting
adjacent windings 106 of the coil 102.
[0048] As shown in FIG. 13a, the structure 98 can include an outer
tubing or sheath 520. The outer tubing 520 can provide an outer
surface 1300 of the structure 98 that can be, for example,
hydrophobic and lubricious. The outer surface 1300 can be a
lubricious material, such as Teflon, for example. The outer tubing
520 can be produced of a polymer, which can include polyethylene,
polyvinyl chloride (PVC), Pebax, silicone, co-polymers, and other
polymers. The outer tubing 520 can be heat shrunk over the coil 102
into tight engagement with the coil 102 and the overall structure
98. Alternatively, the outer tubing can be secured to the coil with
an adhesive applied on the outer surface of the coil or at various
affixation points on the outer surface of the coil. The adhesive
can be a thermo-plastic adhesive that softens at the temperature
necessary to heat shrink the outer tubing.
[0049] The structure 98 can include an inner core 1302 which can be
solid or hollow, as shown in FIG. 13b. The inner core 1302 can
include a working channel lumen 1304. The inner core 1302 can
contain additional reinforcing material to further control
flexibility and torqueability of the structure. The inner core 1302
can be produced of a polymer, which can include polyethylene,
polyvinyl chloride (PVC), Pebax, silicone, co-polymers, and other
polymers.
[0050] Coil structures according to the invention have a variety of
advantages over known structures. Although a welded or joined coil
structure in accordance with the invention may be less flexible
than a plain coil that is unwelded or unjoined, such as the plain
coil shown in FIG. 2, a coil structure according to the invention
(such as the embodiments shown in and described herein with
reference to FIGS. 3, 5, 6a-6e, 7, 8, 9, 10a and 10b, 11, 12, and
13a and 13b) can transmit torque effectively. This ability to
effectively transmit torque tends to enhance the pushability and
steerability of a medical device which incorporates a coil
structure according to the invention as the device or at least a
distal end or distal portion of the device where the inventive coil
structure is located is advanced through body pathways 504 of a
human or other mammal. For example, as shown in FIG. 8, the coil
structure can transmit torque 302 along the welds 322 connecting
adjacent windings of the coil and yet also can be flexed 300 along
unwelded portions of the windings of the coil. In contrast, a plain
coil typically does not transmit torque well as it is rotated.
[0051] While certain embodiments according to the invention are
shown and described, other embodiments are within the scope of this
disclosure and are considered to be part hereof. The invention is
not to be limited just to certain embodiments shown and/or
described.
* * * * *